1. Field of the Invention
The present invention is related to connecting devices across a network, and more particularly to a system and method for mapping virtual ports.
2. Background Information
Computers include a number of ports. Ports are used to connect to external devices. Today, ports are defined for specific machines. Ports include serial ports, parallel ports, USB ports and USB hubs; the terminology may also be extended to include other device ports like audio ports, video ports, parallel ports, compact flash ports, etc.
A virtual port is a port which, although located remotely across a network or a bus, appears to be a local port on a computer. The operating system on the computer receives commands for the virtual port and redirects the commands across the network or bus to the remote port. Typically, these ports are enumerated by a sequential convention within the operating system.
Currently, virtual ports are defined for specific machines. Digi International's RealPort software, for instance, assigns a virtual port to a specific desktop. For example, within the context of RealPort COM10 on a device server might be configured to appear to be COM1 for a specific desktop while COM11 from the same device server might appear to be COM1 for a different desktop. This functionality is described in U.S. Pat. No. 6,047,319, entitled “Network Terminal Server with Full API Implementation,” issued Apr. 4, 2000 to Olson, the description of which is incorporated herein by reference.
When a system administrator adds additional virtual ports, maintaining the mapping of the virtual ports becomes overly complicated. In addition, it can be difficult to move users or applications from one machine to another. If, for instance, the device connected to COM10 is needed by a particular user and that user moves to a different machine, the RealPort software has to map COM10 to the new machine. What is needed is a system and method for mapping virtual ports that solves this problem, and other problems that will become apparent in view of the discussion below.